Development of an organism requires the successive generation of specialized tissues. The plant epidermis is a particularly interesting tissue because it one of the first to be established, yet it continues to differentiate throughout the life of the plant, undergoing specialization to take up nutrients, optimize photosynthetic yields, and ensure reproductive success. The objective of this study is to identify molecules required for the initial formation of the epidermis and later for the development of one set of specialized epidermal types, the ovule integuments. The approach will be to identify, by mutation, (1) genes that are required for the correct localization of an epidermally-expressed reporter gene in the embryo, and (2) genes required for the specification of the integuments by screening for mutants that disturb seed shape and mucilage production. The mutants will be characterized with respect to their role in several epidermal patterning decisions, and the most interesting ones cloned. The information garnered by the analysis of these mutations will suggest ways in which a tissue initiates, expands and maintains its identity. This information may reveal regulatory circuits that are common to the establishment of other tissue types, or it may show that the epidermis has unique developmental patterns that relate to its functional role as the interface between the plant and the outside world. For the improvement of crop plants, knowledge about the epidermis is particularly relevant for the understanding and engineering of plant defenses and for production of plant biomaterials.